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THE ROYAL SOCIETY OF CANADA 



TABLE I 

 Critical K Series Absorption Wave-lengths 



The curve No. 1 corresponding to the numbers in Table I is 

 shown in Fig. 2. 



From the form of the curve (1) it is evident that for the elements 

 cited from potassium to lithium, the square roots of the critical 

 potentials are very closely proportional to the respective atomic 

 numbers, that is, the Moseley law applies. For helium and hydrogen 

 the square roots show only a slight departure from the linear relation 

 which goes to confirm the view that it is now customary to take 

 regarding the spectrum of hydrogen, namely, that the Lyman series 

 is the K series for this element. From the curve and the values given 

 in Table I, it would appear that the critical absorption wave-lengths 

 of the K X-ray series for silicon, sodium, neon, and fluorine, which 

 have not as yet been found experimentally, should be 6.73 XlO~^ cm, 

 11.46X10"^ cm, 14.46 X10~^ cm and 18.4 XlO~^ cm respectively. 



B. Low Range Critical Potentials and L Series Spectra 



Lithium 



With lithium a well marked critical potential was found at 

 12 volts, which, in the light of Bohr's discussion of the structure of 

 the atom of lithium, was taken to be the quantum equivalent of the 



